Effect of polypropylene fiber and nano-zeolite on stabilized soft soil under wet-dry cycles

• Published in: Geotextiles and geomembranes Vol. 49; no. 6; pp. 1470 - 1482
• Main Authors: Akbari, Hamid Reza, Sharafi, Hassan, Goodarzi, Amir Reza
• Format: Journal Article
• Language: English
• Published: Essex Elsevier Ltd 01.12.2021; Elsevier BV
• Subjects: Compressive strength; Durability; Fiber; Impact analysis; Lime; Lime soil stabilization; Macrostructure; Nano-zeolite; Polypropylene; Soft soil; Soil lime; Soil stabilization; Studies; Tensile strength; Weight loss; Wet-dry cycle; Zeolites; Nano-zeolite; Lime; Wet-dry cycle; Soft soil; Fiber
• ISSN: 0266-1144; 1879-3584
• DOI: 10.1016/j.geotexmem.2021.06.001

Nano-zeolite was used in the present study as a substitute for a part of lime and then inclusion polypropylene fiber in stabilized soil matrix to develop the soil stabilization method with lime and to improve the efficiency of this technique. In so doing, specimens of soft soil with 5, 10 and 15% of modifier L (lime), LZ (lime-nano-zeolite) and LZF (lime-nano-zeolite-fiber) were prepared, and were subjected to 1–7 wet-dry cycles. Then, microstructure and macrostructure tests were performed on the specimens. The results of the analyses, indicated that the optimal replacement of lime with nano-zeolite would be 40%, and the optimal amount of polypropylene fibers inclusion would be 1% in the stabilized soil matrix. Major reduction in lime consumption would yield a 40% increase in compressive strength and a 21% improvement in durability. The results also showed that the specimen containing 15%LZF would have excellent durability against environmental conditions and very good performance in terms of unconfined compressive strength (UCS), tensile strength and weight loss. Before and after applying 7 wet-dry cycles, the UCS increased by 39% and 16%, respectively. The results of this study indicate that LZF modifier is a suitable option for lime-based stabilization in areas under wet-dry cycles. •Using lime-nano-zeolite-fiber combination as a new method in improving soft soils.•Applying the wet-dry cycle which are a major challenge for soil stabilization projects.•The use of a lime and nano-zeolite compound not only intensified the stabilization process and reduced lime consumption by 40%, but also increased the compressive strength by almost 40%.•The LZF (lime-nano-zeolite-fiber) modifier significantly increased the ductility and energy absorption of the specimens even after the wet-dry cycles.•The LZF modifier is a suitable option for lime-based stabilization in areas under wet-dry cycles.